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This paper describes two methods of electric charge calibration, one based on capacitors and a voltage source, another in a commercial current source. They were compared, and good agreement was found. Strengths and weakness of the two methods are remarked.
A 10 V programmable Josephson voltage standard system has been installed at the National Research Council Canada. The current margins for the first Josephson step at either current polarity are greater than 1 mA. A preliminary direct comparison of this programmable system with a hysteretic Josephson voltage standard is performed at 10 V.
The paper describes a new primary standard of power at mains and audio frequencies developed at the National Measurement Institute Australia. The standard is based on precision transformers and a thermal power comparator. It provides fully automated power measurements with 1-s uncertainties close to 2 µW/VA.
According to the specifications of IEC60040-2, the partial response time for standard divider to measure lightening impulse should within 20ns; the experiment response should within 10ns. If the divider is used in the measurement of chopped wave, the requirements are even more strictly. The critical key in developing a standard divider used in transient measurement and calibration requires compact...
This paper describes the diagnostic measurements involved while performing impulse tests. For most applications during impulse tests, the impulse voltage and impulse current are measured. Because of the nature of impulse test it is very common that Electro Magnetic Interference signals (EMI) are generated. This EMI will influence the measurement results. Therefore these tests are done in a well-shielded...
This paper describes an experimental evaluation of a high precision voltage harmonic analyzer at power frequency under square waveform. The error and uncertainty of the signal generator were calculated to use it as a harmonic reference standard at UTE (Uruguayan designated National Metrology Institute).
This paper analyzes the effect of the burden on the errors of measuring transformers, specifically the influence of the power factor. Standards propose to calibrate these measuring devices using burdens with different power factor, from 0.1 to 1, but nowadays usual working conditions impose unity power factor in all cases. Error variations due to the power factor of the burden have been measured in...
We describe a method to identify and correct slowly decaying transients in electrical measurements which are performed with periodic reversal of current or voltage bias. Such transients may be of different physical origin like, e.g., dielectric absorption in insulators, which often exhibit a 1/t time dependence, or the Peltier effect. We demonstrate the method with data collected in precision resistance...
The development of a current-comparator-based high-voltage reference inductor at the National Research Council of Canada (NRC) for calibrating loss measurement systems of large high voltage shunt reactors is presented. The high voltage reference inductor features an adjustable loss angle equivalent to a power factor from zero to 0.01. It has an uncertainty of less than 10×10−6 in both magnitude and...
A bridge-based mains frequency power standard has been operated at MSL for the last 16 years. Over this time there have been some improvements to the bridge components and some refinements to the procedures used for calibrating the bridge. These changes have reduced the standard uncertainty from 19 µW/W to 11 µW/W at unity power factor.
An AC quantum voltmeter has been developed for precision AC voltage measurements into the kHz range. A special sub-sampling technique is used such that no information of the AC voltage under test is lost. A comparison of the AC quantum voltmeter and an ultra-stable precision waveform generator has been performed. The Allan deviation analysis demonstrates a voltage output stability of 2 × 10−8 in 1...
The paper analyses a real-time compensation method for the improvement of the frequency behavior of measurement transducers already operating or newly installed in transmission and distribution grids. After a brief description of the developed technique, which is based on the identification of a digital filter, attention is focused on the characterization of its performances. To this end, the method...
High voltage capacitance bridge can be calibrated at fixed ratios using traceable standard capacitors. Typical ratios to be calibrated are 10 to 1 and 100 to 1. Substitution method can be used to reduce bridge related errors and uncertainties. When a capacitor under calibration deviates significantly from the reference capacitor, substitution method is not any more applicable and linearity of a capacitance...
This paper describes the development and testing of a power quality reference setup for the calibration of power quality analyzers in full accordance with the IEC 61000-4-30 standard. The setup excels in great flexibility of the test signals and a large range of measurement applications.
We are developing a calibration system for Zener voltage standards using a programmable Josephson voltage standard (PJVS) for the purposes of the reduction in liquid-helium consumption and also the improvement of the calibration performance. The PJVS array is composed of total 524 288 NbN-based Josephson junctions and is cooled with a 10 K compact cooler. For verifying the validity of the system,...
This paper describes the procedure, data processing and results in capacitance measurements using indirect method, deriving the quantity from voltage, electric current and capacitor's charge time. Results obtained with DMM HP 3458A, Agilent 3458A y Fluke 8508A are described.
This paper describes the performance of a new turn-key AC quantum voltmeter, an AC Josephson voltage standard system, used for calibration of common DC and AC voltage standards. The capabilities and handling of the system in an industrial environment were investigated and are discussed here. Several Fluke 5700A series calibrators were tested and their voltage and frequency dependence is characterized...
Three-phase high voltage power standard has been established at National Institute of Metrology, China. The power standard based on high accuracy three-phase power source, which adopts real-time feedback control technology to achieve excellent stability and accuracy output characteristics. Power/energy measurements can be made at three voltage levers, 10kV, 35kV, 110kV, and current up to 1000A. In...
The 10 V Programmable Josephson Voltage Standard (PJVS) system was successfully set up at Center for Measurement Standards (CMS). In order to more precisely evaluate the performance of this system, we directly compared the PJVS system with our conventional JVS (CJVS) system. The comparison result shows excellent agreement between these two systems. The agreement between these two systems at 1.018...
A reference system for on-site calibration and validation of revenue metering systems is realized. The system consists of a three-phase power meter and high-accuracy current and voltage transformers (CTs and VTs). Measurements can be made up to 150 kV (system voltage) and line currents up to 5000 A. The power meter, the CTs, and the VTs were all calibrated. Based on the excellent results of the calibration...
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